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DOWS
Feasibility Studies
ALL
is in a position to supply in-depth
feasibility studies for operators
to select DOWS candidate wells and
design installations. Our strengths
include the following key factors:
- Our experience
with all of the major equipment
manufacturers
- Our independence
from manufacturers enable us to
specify the equipment best suited
to the site-specific situation
- Our experience
with reservoir numerical modeling
- Our experience
with injection zone selection and
testing
- Our experience
with reservoir stimulation
- Our experience
with DOWS post-mortem evaluations
 Click
on the button to the left to view
the seven-part DOWS Feasibility Study
Design Process used by ALL, beginning
with data gathering through the pilot-test,
operator training, and on-going support.
ALL is able to use its
engineering and geological experience
to help the operator choose a DOWS
design.
- Design Options:
DOWS design can be modified to meet
site-specific needs
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Parameters
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Design
Options
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| Oil
Reservoir Parameters |
Productivity
Index, static pressure,
and fluid characteristics
are needed for the design.
If the well is new or
if reservoir conditions
are unstable, this can
be in part addressed
by the inclusion of,
for example, a Variable
Speed Drive. |
| Injection
Zone Parameters |
A
capable injection or
disposal zone is most
important. The initial
static pressure and
injectivity must be
well known. The zone’s
response to any produced
fines must also be included.
A lack of suitable zone
may be overcome by injecting
over the fracture pressure
if sufficient confinement
is present. |
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- Geological Factors:
The geological character of the
producing zone-confining zone-injection
zone system will dictate some aspects
of the DOWS design; for example,
the fracture gradient of the injection
zone may determine the maximum design
pressure. The presence of fractures
will be most important for designing
the DOWS installation.
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Producing
Zone
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- Matrix
pore and pore-throat
geometry
- Secondary
porosity system
- Presence
of fines in the
porosity
(oil phase and water
phase)
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Disposal
Zone
|
- Porosity/Permeability
system
- Lithology
and fracture gradient
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Confining
Zone
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- Thickness and
lithology
- Fracture gradient
- Vertical permeability
- Joints and fractures
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- Monitoring of
Operations: A vital part of
the DOWS process is full-scale monitoring
of operating parameters including
motor operation and operation of
the hydro-cyclone. Dedicated downhole
instrumentation can produce real-time
data such as that below:
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Operating
parameters show borehole
pressure (dark blue)
increasing toward
static reservoir pressure
until breakthrough
occurs on 11/5/98.
After
that point, borehole
pressure exceeds static
when the DOWS is operating.
This would not have
been discovered with
surface data alone.
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The monitoring data, collected at
the surface on a minute-by-minute
basis, can be transmitted to company
offices. Data such as that above can
give warning of approaching problems.
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